Because of their size, SMD devices cannot carry conventional semiconductor codes. So each manufacturer
gives their products an individual code. These codes are usually consist of two or three digits /
letters.
This fact alone can make the device identification a real headache for third party repair organizations.
The above linked pages contain reference to over 4000 devices and I still have more data to add. The
data is as accurate as possible, however I am only human and may have made some mistakes (typo's etc) so
If you spot something that you are not sure about please email me at the address on the index page and I
will be only too glad to check it for you.

If you cannot see the links then you will need to enable java as they are writen in javascript.

To identify a particular SMD device, first identify the package style and note the ID code printed on
the device.
It can also help if you have a device with the same packaging and code as you can do a CT check on the
good device to tell you a bit about the device type you are looking for. For example there are five
devices marked 02, but if you know the device you are looking for is in a SOT23 package you can look it
up on page 0 and locate the device BSX39.

Be warned though, even the same manufacturer may use the same code for different devices, this is
where a CT check or transistor test can ultimately be decisive in part choice.

Lastly, a big thank you to all those who have contributed to these pages especially G4PMK without who's help
I might never have started this part of my site.

Melf DiodesMELFs (Metal Electrode Leadless Face) have metallised terminals at each end of a
cylindrical body and are designed to fit the same footprints as flat components i.e.: 0805
(.08" x .05") and the 0603 (.06" x .03").

Below is a diagram of a MELF package, mini MELF (SOD80) also known as LL-34 or DO-213AA. The larger MELF package is
also known as SM1, LL-41 or DO-213AB. Dimensions are for indication purposes only as they will vary slightly
from manufacturer to manufacturer.